diff options
Diffstat (limited to 'mm/hwpoison-inject.c')
| -rw-r--r-- | mm/hwpoison-inject.c | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c index ac692a9..2b6b320 100644 --- a/mm/hwpoison-inject.c +++ b/mm/hwpoison-inject.c @@ -3,16 +3,53 @@ #include <linux/debugfs.h> #include <linux/kernel.h> #include <linux/mm.h> +#include <linux/swap.h> +#include <linux/pagemap.h> #include "internal.h" static struct dentry *hwpoison_dir; static int hwpoison_inject(void *data, u64 val) { + unsigned long pfn = val; + struct page *p; + int err; + if (!capable(CAP_SYS_ADMIN)) return -EPERM; - printk(KERN_INFO "Injecting memory failure at pfn %Lx\n", val); - return __memory_failure(val, 18, 0); + + if (!pfn_valid(pfn)) + return -ENXIO; + + p = pfn_to_page(pfn); + /* + * This implies unable to support free buddy pages. + */ + if (!get_page_unless_zero(p)) + return 0; + + if (!PageLRU(p)) + shake_page(p); + /* + * This implies unable to support non-LRU pages. + */ + if (!PageLRU(p)) + return 0; + + /* + * do a racy check with elevated page count, to make sure PG_hwpoison + * will only be set for the targeted owner (or on a free page). + * We temporarily take page lock for try_get_mem_cgroup_from_page(). + * __memory_failure() will redo the check reliably inside page lock. + */ + lock_page(p); + err = hwpoison_filter(p); + unlock_page(p); + if (err) + return 0; + + printk(KERN_INFO "Injecting memory failure at pfn %lx\n", pfn); + return __memory_failure(pfn, 18, MF_COUNT_INCREASED); } static int hwpoison_unpoison(void *data, u64 val) |